The present invention is based on a device for detecting the movement of a movable component of the type including a first position sensor which puts out a signal that is assigned to at least a first position range and a second position sensor which puts out a signal that is assigned to at least a second position range.
The in-house publication by PHILIPS, Philips Semiconductors, entitled KMI 10/1 Integrated Rotational Speed Sensor, SC 17, September 1992, discloses a sensor which detects the number of revolutions of a rotating component. The sensor element employed is a Hall sensor whose output signal is fed to a signal processing arrangement. The signal processing arrangement includes a filter for suppressing electromagnetic interference signals, an amplifier and a Schmitt trigger. The output signal of the Schmitt trigger switches a current source which admits a defined current between two current supply terminals. A further current source is included in the energy supply circuit of the sensor. The further current source keeps the current required to supply the sensor with energy at a constant value. An evaluation arrangement, not described in greater detail, evaluates the current flowing through one of the two current supply lines. The evaluation arrangement converts the change in current impressed by the switched current source, which is actuated by the Schmitt trigger, in one of the current supply lines into a number of revolutions signal.
German Utility Model Patent DE-U 90 12 217.8 discloses an arrangement which includes an electric motor drive for opening and closing the windows in a motor vehicle. A central device equipped with control and evaluation arrangements is connected with several drive units which are disposed in the doors of the motor vehicle. The drive units include an electric motor and a sensor arrangement. The sensor arrangement detects the number of revolutions of the drive. Five connecting lines are provided between the central device and each drive unit for the transmission of signals and energy.